Dataset to text file

Question

User-1068576637 posted

How to  extract text file from dataset  in VB.net . I tried below code but takes too much time.  Is there any other solution available ?

Instead of loop it should be instance file.

'txt += vbCr & vbLf

If ds.Tables(0).Rows.Count > 0 Then

For Each row As DataRow In ds.Tables(0).Rows

For Each column As DataColumn In ds.Tables(0).Columns

'Add the Data rows.

txt += row(column.ColumnName).ToString() & vbTab & vbTab

Next

'Add new line.

txt += vbCr & vbLf

Next

fp.WriteLine(txt)

fp.Close()

Answer 1

User-939850651 posted

Hi Mohammed Tajudeen,

Based on the code you provided, I think the main problem is unnecessary loop nesting.

For Each column As DataColumn In ds.Tables(0).Columns

'Add the Data rows.
txt += row(column.ColumnName).ToString() & vbTab & vbTab

Next

When you traverse to each row of the same dataTable ( Tables(0) ), you will execute this loop, and it will get the same result. Therefore it is redundant, and it will reduce your operating efficiency.

I think you can move this part out of the outer loop, define the result as a variable and just use it. Something like this:

'txt += vbCr & vbLf
Dim columnNales as String

For Each column As DataColumn In ds.Tables(0).Columns
    'Add the Data rows.
    columnNales += row(column.ColumnName).ToString() & vbTab & vbTab
Next

If ds.Tables(0).Rows.Count > 0 Then
    For Each row As DataRow In ds.Tables(0).Rows
        'Add new line.
        txt += columnNales & vbCr & vbLf
    Next
fp.WriteLine(txt)
fp.Close()
...
End If

Best regards,

Xudong Peng